title: Strategies for the prevention of postoperative recurrence of Crohn's disease.
abstract: OBJECTIVE
  To review the optimal strategy to prevent recurrence of Crohn's disease (CD) after surgery, with particular emphasis on the risk factors that predict postoperative recurrence, methods of monitoring for recurrence and medications used to prevent postoperative recurrence.
  
  
  METHODS
  MEDLINE and the Cochrane Library were searched for clinical trials and meta-analyses that studied postoperative recurrence and prophylactic medications in CD.
  
  
  RESULTS
  The most significant factor that predicted postoperative recurrence was patient smoking status. Smokers had an increased risk of recurrence (odds ratio = 2.15; 95% confidence interval (CI) = 1.42-3.27). Similarly, perforating CD appeared to be associated with a higher recurrence rate compared with nonperforating CD (hazard ratio = 1.50; 95% CI = 1.16-1.93). The optimal monitoring strategy for postoperative recurrence has yet to be established. Nonetheless, ileocolonoscopy is considered to be the gold standard. Noninvasive imaging techniques including contrast ultrasonography and capsule endoscopy appear to be useful for postoperative monitoring. A number of meta-analyses found that mesalazine, nitroimidazole antibiotics and purine analogues (azathioprine/6-mercaptopurine) significantly reduced the risk of postoperative recurrence when compared with placebo. Additionally, recent randomized controlled trials have suggested that an early intervention with infliximab is likely to prevent recurrence after ileocolonic resection. Likewise, in prospective studies, biological therapy (infliximab/adalimumab) reduced clinical and endoscopic CD activity in patients with early endoscopic recurrence after surgery.
  
  
  CONCLUSIONS
  Although additional evidence is necessary, endoscopic monitoring and treatment step-up should be used to prevent postoperative recurrence of CD.
authors.affiliation: Inflammatory Bowel Disease Centre and Department of Surgery, Yokkaichi Social Insurance Hospital, Yokkaichi, Mie, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Yamamoto
authors.forename: T
authors.initials: T
authors.lastname: Watanabe
mesh_terms: D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000627:therapeutic use*; D000911:Antibodies, Monoclonal / Q000627:therapeutic use; D001379:Azathioprine / Q000627:therapeutic use; D003082:Colectomy; D003106:Colon / Q000601:surgery*; D003113:Colonoscopy; D003424:Crohn Disease / Q000188:drug therapy / Q000517:prevention & control* / Q000601:surgery; D006801:Humans; D007082:Ileum / Q000601:surgery*; D007166:Immunosuppressive Agents / Q000627:therapeutic use*; D000069285:Infliximab; D007416:Intestinal Perforation; D015122:Mercaptopurine / Q000627:therapeutic use; D019804:Mesalamine / Q000627:therapeutic use; D009593:Nitroimidazoles / Q000627:therapeutic use; D016017:Odds Ratio; D016016:Proportional Hazards Models; D012307:Risk Factors; D055502:Secondary Prevention; D012907:Smoking; D016896:Treatment Outcome
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D000911:Antibodies, Monoclonal; D007166:Immunosuppressive Agents; D009593:Nitroimidazoles; D019804:Mesalamine; D000069285:Infliximab; D015122:Mercaptopurine; D001379:Azathioprine
keywords: Crohn's disease; biologic agents; ileocolonoscopy; postoperative recurrence; prophylactic medication